The subject matter of the invention is a storage container for radioactive material, especially for spent fuel elements, including a base body provided with a cover, a jacket surrounding the cover and the base body on the outside and made of a corrosion-resistant material and a carrying device in the form of a lifting lug.
For the transportation and storage of heat producing radioactive substances such as, for example, spent fuel elements from nuclear power plants or waste matter from installations for the reprocessing of spent fuel elements, containers are used in which the radioactive substances are safely enclosed, from which the heat produced may be carried away safely at any time and which are critically safe.
Customarily, thick-walled containers are used which are lined on the inside with high-grade steel. Whenever the containers are to be stored underground, for example in shut down mines, then the walls of the container must be able to absorb the mechanical forces that may result from a collapse of the mine walls and must be corrosion-resistant. For reasons of economy, multilayer containers containing a base body and a jacket are used in such cases. For the base body, normally a heat-resistant, reasonably priced material is used which does not need to be corrosion resistant, since it does not come into contact with corrosive media. The container will be dimensioned in such a way, that it withstand the pressure from a mine collapse. It must be configured so that the bottom and the cover lid may be inserted or screwed in tightly.
For the jacket, corrosion-resistant materials are used. In salt mines, in which the occurrence of quinary liquors, must be taken into account, highly alloyed steels or steels on the basis of zirconium or titanium come into question.
Such containers usually contain storage cans in which the radioactive matter is placed and they are inserted on their part into shielding containers, at least during the transportation and possibly an intermediate storage. The cover of the multilayer container is provided with a fixedly mounted carrying peg by which the multilayer container is lifted and inserted into the shielding container and may possibly again be taken out of it. The minimal height of the carrying peg amounts to about 15 to 20 cm. One disadvantage of this fixedly mounted carrying peg consists in the fact that the shielding container will have to be made longer by this height. This increases the overall weight and makes the shielding container considerably more expensive. In addition, it will be necessary that the weighty carrying peg is made of the same, very expensive, corrosion-resistant material, as the corrosion-safe outside jacket in order to avoid local element formation and the like. That, too, has a disadvantageous effect as far as weight and costs are concerned. A further disadvantage is the practically point-like load on the cover below the fixedly mounted carrying peg in case of the crash of a container. The same is true naturally also for the storage cans contained in the multilayer container insofar as they are also provided with fixed carrying pegs of similar handling devices.